AC/DC power converters used to convert an AC voltage to a constant DC electric signal (DC voltage and/or DC current) are widely applied to drive loads of relatively high power (e.g., electric motors, light-emitting diode [LED] lamps, etc.). A rectifying bridge is usually configured in an AC/DC power converter to convert an external AC voltage to a half-sinusoid DC voltage for a subsequent converting circuit. Also, a power factor correction (PFC) circuit may be utilized in an AC/DC power converter to achieve power factor correction to obtain a relatively high power factor.